This invention generally relates to retaining devices and more particularly to a bi-directional retainer for releasably securing wheelchair accessories to a wheelchair frame.
Most modern wheelchair are foldable or collapsible to facilitate transportation and storage. Such chairs are usually equipped with a rigid seat and back rest which must be removed before the chair can be collapsed. Means must be provided for securely attaching the seat and back rest to the chair while permitting them to be quickly and easily removed. Ideally those attachment means should be easily accessible to the user of the chair or an attendant and should be operable without tools of any sort. They should also be designed to minimize the possibility of accidental disengagement of the seat or back rest. Finally, they should be adaptable for use on existing wheelchair frames and with the J hook type support brackets which are commonly used to attach seats and backs to the frames.
One problem with the design of many attachment devices in the prior art is that they must be mounted to the wheelchair frame in a particular orientation with respect to the seat (or back rest) and its support brackets. Such devices normally require the use of pairs of symmetrically designed components on the frame. As a result such devices are inherently more expensive to manufacture than one consisting of identical and interchangeable components.
Accordingly, it is an object of this invention to provide a bi-directional retainer for attaching a seat and a back rest to a wheelchair and in particular a foldable or collapsible type wheelchair.
Another object of this invention is to provide for such a retainer which will minimize the possibility of an accidental or inadvertent release of the seat or back rest from the wheelchair frame.
Another object of this invention is to provide for such a bi-directional retainer which can be adapted to various wheelchair configurations without significant modifications to the chair.
It is yet a further object of this invention to provide for such a retainer which can function when mounted on either side of a typical J hook seat bracket thereby reducing manufacturing costs by eliminating the need for the use of symmetrical pairs of retainers.
This invention can be broadly summarized as providing for a bi-directional retainer for removably securing a seat, a back rest or other accessories to a wheelchair frame. The retainer includes a base, a slide mounted on the base for movement between two spaced operating positions and a means for biasing the slide toward one of those operating systems when the slide is displaced toward a desired operating position from a neutral position located in between the two operating positions.
In accordance with a more detailed aspect of the invention the slide is mounted on a track attached to the base and the biasing means includes a spring. The frame also includes means for mounting the base on a wheelchair frame.
In accordance with a yet more detailed aspect of this invention the base includes a pair of parallel oriented tracks and the slide is mounted on the tracks for movement between the two operating positions. Also the retainer includes a mounting clamp having a leg fixed to the base, a second leg pivotally mounted to the base and a screw for adjustably connecting the first and second legs.